In addition, the ET domain–binding motif, which shares similar amino acid sequences from other BRD4-ET–binding proteins such as CHD4 and NSD2/3, also mediates interaction of BRD4-ET with ASXL3 and functionally links BRD4 to the BAP1 complex in a small-cell lung cancer (SCLC) subtype (Szczepanski, 2020). Here, BRD4 is linked to small cell lung carcinoma.